Lowry K J, Hamson K R, Bear L, Peng Y B, Calaluce R, Evans M L, Anglen J O, Allen W C
Department of Orthopaedic Surgery, University of Missouri-Columbia 65212, USA.
J Biomed Mater Res. 1997 Sep 15;36(4):536-41. doi: 10.1002/(sici)1097-4636(19970915)36:4<536::aid-jbm12>3.0.co;2-8.
Research in improved materials and methods for internal fixation has centered on internal fixators made of bioabsorbable materials such as polylactic acid, polyglycolic acid, and polyparadioxanone. These materials have two problems: the first is a postoperative complication related to a delayed inflammatory response; and the second is low strength characteristics. An alternative material developed to alleviate these problems is a composite of phosphate glass fibers embedded in the polymer polycaprolactone, referred to as PCL. In this study, intramedullary pins made of PCL were compared to stainless steel pins in a rabbit humerus osteotomy model. Specimens were harvested at 0, 6, and 12 weeks postoperatively, radiographs and mechanical testing to failure were performed at each time interval, and tissue was examined microscopically at 6 and 12 weeks. Histologic results showed PCL pins to be well tolerated with minimal inflammation around the pin. Mechanical testing revealed the PCL fixation to be weaker initially than the stainless steel fixation. There was significant stress shielding of stainless-steel-healed rabbit humeri when compared to the PCL/bone humeri. All osteotomies immobilized with PCL healed with abundant periosteal callus production.
关于改进内固定材料和方法的研究主要集中在由生物可吸收材料制成的内固定器上，如聚乳酸、聚乙醇酸和聚对二氧环己酮。这些材料有两个问题：第一个是与延迟炎症反应相关的术后并发症；第二个是强度特性较低。为缓解这些问题而开发的一种替代材料是嵌入聚合物聚己内酯中的磷酸盐玻璃纤维复合材料，称为PCL。在本研究中，在兔肱骨截骨模型中，将由PCL制成的髓内针与不锈钢针进行了比较。术后0、6和12周采集标本，在每个时间间隔进行X线片检查和机械测试直至失效，并在6周和12周时进行组织显微镜检查。组织学结果显示PCL针耐受性良好，针周围炎症轻微。机械测试表明，PCL固定最初比不锈钢固定弱。与PCL/骨的肱骨相比，不锈钢愈合的兔肱骨存在明显的应力遮挡。所有用PCL固定的截骨均通过大量骨膜骨痂形成而愈合。
